Apparatus for the combustion of fuel



Feb. 1, 1955 C. A. BONVILLIAN ET AL APPARATUS FOR THE COMBUSTION OF FUELFiled March 15, 1950 a w y 4 m m i o WZrQW I W 1 1. A 9 f e 1 UnitedStates Patent APPARATUS FOR THE COMBUSTION OF FUEL Claude AlbertBonvillian, Chattanooga, Tenn., Ralph C. Brierly, Narberth, Pa., andSamuel Letvin, Elmhurst,

Original application August 26, 1944, Serial No. 551,420. Divided andthis application March 15, 1950, Serial No. 149,848

1 Claim. (Cl. 158-106) (Granted under Title 35, U. S. Code (1952), sec.266) This invention pertains to the combustion of fuels and othervaporizable and combustible substances. The present application is adivision of copending application of Claude A. Bonvillian et al., SerialNo. 551,420 filed August 26, 1944, for Apparatus for the Combustion ofCombustible and Vaporizable Substances, now Patent No. 2,601,242.

The invention provides novel means for the combustion of fuels and othersubstances, preferably at relatively high heat releases, andparticularly apparatus for changing the state of aggregation ofcombustibles and vaporizable substances and distributing them to assuremore complete combustion. The invention is applicable to a wide varietyof uses such as disc, grid or ring burners, gas turbine systems, fluidheaters, rocket or jet propulsion devices,'vapor generators, fogdispelling apparatus and apparatus for drying, smelting, .sintering orbaking. Apparatus of the invention, through the distribution of thecombustibles or vaporizable substances, flame dispersion andapportionment obtainable therewith, permits furnaces or other devices ofwhich it is a part to be of more compact construction and lighter weightthan hitherto practicable.

Apparatus embodying and for carrying out the invention comprises meansto facilitate vaporization, gasification, raising to or beyond firepoint, or otherwise greatly increasing the combustibility and potentialcombustion speed of fuel oil or other combustible or vaporizablesubstance fed into the stream of gases of combustion. Furnaces suitablefor the purpose are disclosed in our copending applications Serial No.479,010 filed March 13, 1943, now Patent No. 2,500,925, Serial No.506,670 filed October 18, 1943, now Patent No. 2,569,446; and Serial No.509,080 filed November 5, 1943, now Patent No. 2,464,791. Althoughfurnaces of many types other than those disclosed in these copendingapplications may be used to carry out the invention, the furnacesdisclosed therein have the advantages of requiring but a relativelysmall space and of being of a minimum weight. The substance to be burnedor vaporized is introduced into con tact with the stream of gasesproduced in the furnace preferably by nozzles connected to a manifold,as disclosed in our copending application Serial No. 509,080 filedNovember 5, 1943, now Patent No. 2,464,791, or through injectors at thefurnace exit. If the substance is in a liquid or solid state, it isvaporized or otherwise prepared for high speed combustion either by thehot gases in or from the furnace, by contact with adjacent parts of thefurnace which have become heated by gases, by the injectors which may beheated from the furnaces combustion chamber, or by distributingapparatus beyond the combustion chamber throat which is heated to a highdegree. Any one or more of these methods of vaporization may be used.After vaporization of the substance and its mixture with gases ofcombustion, the mixture is ejected, preferably at high velocities,through the exit nozzles of distributing devices. Relatively high airpressure is employed in the furnaces windbox to serve the function of(l) furnishing oxygen for combustion; (2) supplying sufficient force tointermix the substance or substances raised to or beyond the fire pointor otherwise prepared for virtually instantaneous ignition; (3)distributing the mixture of substances to individual nozzles of adistributing device; (4) maintaining a high velocity "ice through thesenozzles; and (5) aspirating surrounding air by the gas-vapor issuingfrom the nozzles. Localization of the aspirating effect may be obtainedby using hollow rings or polygonal-shaped registers around individualdistributing devices, around a group of distribuiting devices or arounda single nozzle of a distributing device. The distributing devices maybe entirely enclosed by air ducts or have air ducts positioned on one ormore sides thereof.

Perfection of these devices will depend upon the optimum proportioningof the parts to assure maximum advantages from all of these variables.The spacing and the arrangement of the nozzles of the distributingdevices, as well as their free areas, are important considerations. Alsooptimum proportioning of air admitted to, around, or alongside thenozzles is desirable, lest the quantity or velocity either be inadequateor plethoric which would result in incomplete oxidation, blowing out, orundue dilution of the stream from the nozzles. Regulation of air flowsurrounding the nozzles is a matter of importance in connection withlighting olf the mixture of gas and air at the face or faces of thedistributing devices. It is frequently desirable temporarily to halt orgreatly to diminish air flow while initial ignition is being secured,then to advance it to support increased flow rates and combustion speed.Substances, whether liquid or solid, or in any other state ofaggregation, may be employed for feeding the distributor of distributingdevices although satisfactory results can be secured through the use ofthe same material as that used for firing the furnace. Another importantconsideration is the apportionment of the injectors used to supply thesubstances to the vaporized, raised beyond the fire point or otherwiseprepared for high speed combustion, either to the furnace or thedistributing devices of the present invention, since the rate of flowfrom the nozzles depends upon such apportionment as Well as upon thearea of the nozzles and speed of travel of the mixture expelled from thefurnace exit.

The invention will be understood from the following description whenconsidered in connection with the accompanying drawings forming a partthereof and in which:

Fig. 1 is a more or less diagrammatic view in elevation, of a form ofthe invention which is suitable for firing a boiler; and

Fig. 2 is a bottom view of part of the apparatus shown in Fig. l, on anenlarged scale.

Like characters of reference refer to the same or to similar partsthroughout the several views.

Referring to Figure 1 of the drawings, reference character 10 designatesthe furnace which comprises an outer metallic casing 11, having acylindrical windbox 13 from which air is supplied thereto. Fuel issupplied under pressure to the furnace 10 through a line 25, and air forthe windbox 13 is supplied by a blower or compressor 13' coupled to thefurnace through the conduit 26.

In the form of the invention shown in Fig. 1, a suitable combustible orvaporizable substance, is introduced to atomizers 28 and 29 whichdischarge into a cylindrical spool piece 30, connected to the outlet endof the furnace 10. This substance is fed to the atomizers under pressurefrom a pump, not shown, through connecting conduits 30'. The combustiongases flowing through the spool piece 30 possess reasonable homogeneityof constituents and temperatures, and vaporize the substance, raise itto and beyond the fire point, or otherwise prepare it for almostinstantaneous ignition after discharged by the distributing means to bedescribed. Grids 31 may be positioned in the spool piece which grids areof heavy screen or grating and extend entirely across the area of thespool piece immediately below the point at which the atomizers dischargethereinto. The grids 31 prevent precipitation into the furnace 10 of anyresidual material which may otherwise drop downwardly therein. They alsoassist in heating the substances to be vaporized, gasified or otherwiseraised to or beyond the fire point and are particularly advantageous inthe heat ing of crude oil, blends or mixtures of coal and oil since theyincrease turbulence of the substances and the extent of travel thereof.The mixture of heated materials is then passed through a conduit 51 or52 into a distributor hereinafter disclosed.

Thus, in the preferred embodiment of the invention illustrated in Fig.1, the gases are distributed from the grid-like structure. Thisstructure comprises a plurality of longitudinally extending manifolds49, each having a plurality of nozzles 50 spaced axially along themanifolds, the nozzles in one manifold being arranged in staggeredrelationship with the nozzles in adjacent manifolds. The manifolds 49are in communication at opposite ends thereof with conduits 51 and 52respectively. The conduit 51 is connected at one end thereof to thespool piece 30 of the furnace 10, while the conduit 52 is connected atthe opposite end to the spool piece 30 of a furnace so that the furnaces10 and 10' are disposed at opposite ends of the grid-like structure.Each nozzle 50 is surrounded by a hexagonal shaped air register 53 Whichprojects outwardly from the side of the manifold 49 and forms a forwardor discharge end and also protrudes from the opposite side of themanifold to form a rear open-end. Air is introduced into the registers53 through the rear end thereof preferably from an air casing 53" towhich air is supplied under pressure through a conduit 53. The aircasing 53" is secured to the rear open-end of the grid-like structurethrough a pair of lon itudinal bracing members 35 extending betweenconduits 51 and 52 and secured thereto in parallel relationship to themanifolds 49 and at opposite sides thereof. The quantity of air suppliedto the registers is controlled by shutters or dampers 54 which closeagainst the rear ends 37, as shown in Figure 2 of the registers. Theshutters 54 are fixed on revoluble shafts 55, rotatably mounted onbracing members 35, which are rotated about their axes to move theshutters toward opened or closed position, by means of gears 56 mountedon the lower ends of the shafts, and meshing with each other as shown.As shown in Fig. 1, the gears 56 are actuated to move the shutters 54,by a reversible electric motor M. It will be understood that other typesof dampers may be used and that the dampers may be controlled manuallyor automatically by other driving means if desired. Registers of shapesother than hexagonal may be used, although hexagonal-shaped registersprovide the desired structural strength and rapid air intermixture.

In the operation of the preferred embodiment of the invention, gasesfrom the spool piece 30 connected to the furnace 10 flow into conduit 51and into the manifolds 49, the greater proportion of the gases flowinginto the manifolds at the end of the grid-like distributing structurenearest the furnace 10. Similarly the gases from the furnace 10 flowinto the conduit 52 and into the ends of the manifolds 49. With thisarrangement, gases from the furnaces 10 and 10' are distributedsubstantially equally among the manifolds 49. The gases are ejected fromthe manifolds 49 by the nozzles 50. The admission of air into theregisters 53 is controlled by the shutters 54, the arrangement belngsuch that the rear end of the registers are closed when the highlyheated inflammable substances are initially emitted from the nozzles 50but are opened immediately upon issuance of flame.

The invention disclosed herein may be manufactured and used by or forthe Government of the United States for governmental purposes withoutpayment of royalty thereon, or therefor.

It will be understood that changes may be made in the form, location andrelative arrangement of the several parts of the apparatus disclosedherein without departing from the principles of the invention.Accordingly, the invention is not to be limited excepting by the scopeof the appended claim.

We claim:

In a gas combustion assembly, a gas distributing apparatus comprising apair of parallel gas feeding conduits, a plurality of longitudinallyextending manifolds connected to said gas feeding conduits to therebyform a grid-like structure, each of said longitudinally extendingmanifolds being parallel to each other and having a plurality of equallyspaced gas nozzles located along its length, said gas nozzles of eachadjacent longitudinally extending manifold being positioned in staggeredrelationship to each other, a hexagonal shaped air register surroundingeach of said gas nozzles and projecting outwardly from the gas nozzleside of said grid-like structure to form a discharge end, each said airregister protruding from the side of the grid-like structure oppositesaid gas nozzle side and adapted to form a rear openend, a pair oflongitudinal bracing members extending between said pair of parallel gasfeeding conduits and secured thereto in parallel relationship to saidplurality of longitudinally extending manifolds and at opposite sidesthereof, a plurality of revoluble shutter shafts secured to said pair oflongitudinal bracing members on the side opposite said gas nozzles andperpendicular to said longitudinally extending manifolds, a plurality ofshutters fixed to said shutter shafts behind each of said gas nozzlesand said air register, actuating means, and gear means coupling saidshutter shafts to each other and to said actuating means.

References Cited in the file of this patent UNITED STATES PATENTS240,592 Houchin Apr. 26, 1881 508,410 Cowles Nov. 14, 1893 629,882Windham Aug. 1, 1899 1,551,532 Axtell et a1. Sept. 1, 1925 1,599,015Jackson et a1. Sept. 7, 1926 1,712,881 Gibson May 14, 1929 2,386,882Reagan et al Oct. 16, 1945 2,559,979 Martois July 10, 1951 FOREIGNPATENTS 311,588 Germany Mar. 27, 1919

